1. Field of the Invention
The present invention relates to a performance control apparatus that sequences data of a music piece for a predetermined duration according to operation by a performer, as well as a storage medium for the performance control apparatus.
2. Description of the Related Art
Conventionally, there have been known electronic musical instruments that generate musical tones in response to operation by a performer. Such electronic musical instruments are modeled on, for example, pianos and generally carry out performance operations in a manner similar to pianos that are acoustic musical instruments. These electronic musical instruments require skill to perform and much time to learn.
In recent years, however, realization of musical instruments that can played with ease by unskilled persons has been desired, and for example, an electronic musical instrument disclosed in Japanese Laid-Open Patent Publication (Kokai) No. 2000-276141 (Prior Art 1) has been proposed. The electronic musical instrument of Prior Art 1 is configured to carry out automatic performance to sound musical tones of certain duration (for example, about a half measure) in response to a simple operation (for example, shake by hand) by a performer. The electronic musical instrument of Prior Art 1 is comprised of a plurality of slave units and one master unit.
Such an electronic musical instrument generates musical tones in accordance with operation by a performer. Specifically, when a performer carries out a performance operation using operators, information indicative of the intensity of the performance operation (hereafter referred to as “beat velocity” in this specification) is transferred from one of the slave units to the master unit. The master unit reads out musical tone data of a part assigned to the slave unit and determines, for example, the tone color of musical tones based on the above-mentioned beat velocity and intensity information (hereafter referred to as “musical tone velocity”) written in advance in the musical tone data. The master unit also determines the volume of the musical tones based on volume information written in advance in the musical tone data and sounds the musical tones. It should be noted that electronic musical instruments are generally equipped with an operator (such as a volume slider) for a performer to designate the volume so that musical tones can be sounded with consideration given to the volume designated using the operator.
In the electronic musical instrument of Prior Art 1, once a performer has carried out a performance operation, musical tones of certain duration (for example, about a half measure) are automatically sounded with a tone color determined by this operation. The volume of the musical tones being sounded is determined based on information written in musical tone data. Once sounding of musical tones has been started, the volume thereof is not changed whatever operations a performer carries out. For this reason, it has been impossible to achieve performance expressions such as a gradual increase in tone intensity (crescendo) and a gradual decrease in tone intensity (decrescendo).
To realize increase and decrease in tone intensity, an automatic performance apparatus that can apply performance expressions such as crescendo and decrescendo to a given part of musical tone data has been proposed (Prior Art 2) (see Japanese Laid-Open Patent Publication (Kokai) No. H10-222163, for example). Also, an electronic musical instrument that enables designation of the volume of subpart data by operation of performance operators has been proposed (Prior Art 3) (see Japanese Laid-Open Patent Publication (Kokai) No. 2002-328676, for example).
The automatic performance apparatus of Prior Art 2 is capable of editing musical tone data and changing the velocity (here, musical tone velocity) according to the curve of variations in the volume of musical tones as a whole. Thus, the automatic performance apparatus of Prior Art 2 cannot control the dynamics (volume) of musical tones in real time based on beat velocities designated through operation by a performer.
Also, the electronic musical instrument of Prior Art 3 is capable of changing the volume of a subpart in real time through operation by a performer. However, for example, the electronic musical instrument is not capable of changing the volume of a prolonged musical tone of a main part, that has once been sounded even when the performer carries out an operation during sounding of the musical tone. Thus, as is the case with the automatic performance apparatus of Prior Art 2 mentioned above, the electronic musical instrument of Prior Art 3 cannot control the dynamics (volume) of musical tones in real time based on beat velocities designated through operation by a performer and cannot achieve performance expressions such as crescendo and decrescendo.